During 1981, fatness data from the Bogalusa (Louisiana) Heart Survey will be reduced, converted into age-specific and sex-specific normalized Z scores and made ready for data analysis emphasizing changes in relative fatness overspecified age periods, in family line context, taking fatness levels of remaining family members into account and fatness changes of remaining family members into account. Meanwhile, fatness change data and fatness variability data from the Tecumseh (Michigan) Community Health Survey will be subject to further analysis with respect to fatness change according to fatness change and directions of fatness change for 1, 2, 3, and 4 remaining family members. Changes in socioeconomic status between 1968 and 1980 as well as changes in family composition, marital affinities, domiciliary arrangements and life style will also be considered as major variables bearing on fatness, fatness change, direction of fatness change and variabilities in fatess for husbands and wives, sons and daughters, parent-child pairs and sibling pairs both living together and living apart. As before, comparisons will be made of genetically unrelated individuals living together and of genetically unrelated pairs (husband-wife, parent and adopted child, adopted "siblings").